A rotor of a rotating electric machine includes a rotor yoke, a pair of end plates disposed on both axial sides of the rotor yoke, and a resolver for detecting a rotation angle of the rotor. The rotor yoke is formed by laminating a plurality of core members formed of electromagnetic steel plates in a substantially annular shape and a plurality of magnets forming magnetic pole portions are embedded on an outer circumferential side of the core members. When the rotor of the rotating electric machine is assembled as described above, a positioning pin is inserted through a yoke cavity portion formed in the rotor yoke and an end plate hole portion formed in the end plate, so as to be assembled in a state where positioning is performed so that the phases of the magnetic poles of the magnets and a sensor of the resolver are in predetermined phases.
Further, even after the rotor of the rotating electric machine is assembled, the quality inspection is carried out as to whether the rotor yoke is assembled with the correct phases based on a measuring point set in the yoke cavity portion. In an end plate of a rotor of the related art, a hole for positioning at the time of assembling a rotor yoke and post-assembly inspection and a hole for discharging a coolant are provided for each application.
In JP-A-2011-223717, a manufacturing method of a rotor of an electric motor in which a cooling flow path extending in an axial direction is provided inside a rotor yoke and the rotor is cooled by a coolant flowing through the cooling flow path, and then the coolant is discharged from a hole provided in an end plate, is disclosed.
Generally, according to a rotor of a rotating electric machine of the related art, a hole for positioning at the time of assembly and post-assembly inspection and a hole for discharging a coolant are separately provided in an end plate. Thus, the number of holes to be processed is increased and processing steps are extended, and further accuracy of each hole is required, whereby the cost is increased.
In the manufacturing method of a rotor of an electric motor disclosed in JP-A-2011-223717, there is a description about a cooling flow path of a rotor yoke, but positioning at the time of assembly and post-assembly inspection are not mentioned. Therefore, as similar to a general rotor of the related art, it is considered that a hole for positioning at the time of assembly and post-assembly inspection is provided separately from a hole for discharging a coolant.